Jetlag Expectations, not Circadian Parameters, Predict Jetlag Symptom Severity in Travelers

AbstractAfter a flight across multiple time zones, most people show a transient state of circadian misalignment causing temporary malaise known as jetlag disorder. The severity of the elicited symptoms is postulated to depend mostly on circadian factors such as the number of time zones crossed and the direction of travel. Here, we examined the influence of prior expectation on symptom severity, compared to said “classic” determinants, in order to gauge potential psychosocial effects in jetlag disorder.To this end, we monitored jetlag symptoms in travel-inexperienced individuals (n=90, 18-37y) via detailed questionnaires twice daily for one week before and after flights crossing >3 time zones. We found pronounced differences in individual symptom load that could be grouped into 4 basic symptom trajectories. Both traditional and newly devised metrics of jetlag symptom intensity and duration (accounting for individual symptom trajectories) recapitulated previous results of jetlag prevalence at about 50-60% as well as general symptom dynamics.Surprisingly, however, regression models showed very low predictive power for any of the jetlag outcomes. The classic circadian determinants, including number of time zones crossed and direction of travel, exhibited little to no link with jetlag symptom intensity and duration. Only expectation emerged as a parameter with systematic, albeit small, predictive value.These results suggest expectation as a relevant factor in jetlag experience - hinting at potential placebo effects and new treatment options. Our findings also caution against jetlag recommendations based on circadian principles but insufficient evidence linking circadian re-synchronization dynamics with ensuing symptom intensity and duration.Significance StatementJetlag disorder afflicts millions of travelers each year - a nuisance on holiday trips but also a danger in safety and performance-critical operations. For effective prevention and treatment, it is critical to understand what influences jetlag severity, i.e. jetlag symptom intensity and duration. In contrast to what guidelines state, in our study, we did not find that symptom severity could be explained by the number of time zones crossed or travel direction. Rather, travelers’ expectations about how long and strongly they will suffer from jetlag symptoms was the only factor systematically predicting jetlag severity. If this holds true not only for subjective but also objective symptoms, we need to revisit assumptions about how circadian desynchronization relates to experienced jetlag symptoms.

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Neurobehavioral Symptoms in U.S. Special Operations Forces in Rehabilitation After Traumatic Brain Injury: A TBI Model Systems Study

Military Medicine ◽

10.1093/milmed/usab347 ◽

2021 ◽

Author(s):

Amanda Garcia ◽

Shannon R Miles ◽

Tea Reljic ◽

Marc A Silva ◽

Kristen Dams-O’Connor ◽

...

Keyword(s):

Traumatic Brain Injury ◽

Brain Injury ◽

Symptom Severity ◽

Model Systems ◽

Ptsd Symptoms ◽

Special Operations ◽

Comorbidity Burden ◽

Symptom Intensity ◽

Neurobehavioral Symptoms ◽

Special Operations Forces

ABSTRACT Introduction Special Operations Forces (SOF) personnel are at increased risk for traumatic brain injury (TBI), when compared with conventional forces (CF). Prior studies of TBI in military samples have not typically investigated SOF vs. CF as specific subgroups, despite documented differences in premorbid resilience and post-injury comorbidity burden. The aim of the current study was to compare SOF vs. CF on the presence of neurobehavioral symptoms after TBI, as well as factors influencing perception of symptom intensity. Materials and Methods This study conducted an analysis of the prospective veterans affairs (VA) TBI Model Systems Cohort, which includes service members and veterans (SM/V) who received inpatient rehabilitation for TBI at one of the five VA Polytrauma Rehabilitation Centers. Of those with known SOF status (N = 342), 129 participants identified as SOF (average age = 43 years, 98% male) and 213 identified as CF (average age = 38.7 years, 91% male). SOF vs. CF were compared on demographics, injury characteristics, and psychological and behavioral health symptoms. These variables were then used to predict neurobehavioral symptom severity in univariable and multivariable analyses. Results SOF personnel reported significantly greater posttraumatic stress disorder (PTSD) symptoms but less alcohol and drug use than the CF. SOF also reported greater neurobehavioral symptoms. When examining those with TBIs of all severities, SOF status was not associated with neurobehavioral symptom severity, while race, mechanism of TBI, and PTSD symptoms were. When examining only those with mTBI, SOF status was associated with lower neurobehavioral symptoms, while PTSD severity, white race, and certain mechanisms of injury were associated with greater neurobehavioral symptoms. Conclusions Among those receiving inpatient treatment for TBI, SOF SM/V reported higher neurobehavioral and symptom severity. PTSD was the strongest predictor of neurobehavioral symptoms and should be considered an important treatment target in both SOF and CF with co-morbid PTSD/TBI. A proactive human performance approach towards identification and treatment of psychological and neurobehavioral symptoms is recommended for SOF.

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Synchronous Surgical Treatment of Lower Eyelid Involutional Entropion and Ptosis

Case Reports in Ophthalmological Medicine ◽

10.1155/2018/2478646 ◽

2018 ◽

Vol 2018 ◽

pp. 1-3

Author(s):

D. Vasakos ◽

E. Nakos ◽

C. Sioulis

Keyword(s):

Treatment Options ◽

The Elderly ◽

Lower Eyelid ◽

Postoperative Recovery ◽

Multiple Time ◽

Upper Eyelid ◽

Alternative Treatment Strategy ◽

Involutional Entropion ◽

Lateral Tarsal Strip ◽

Upper Eyelid Ptosis

Background. Involutional entropion and upper eyelid ptosis are common eyelid diseases in the elderly population. They represent a frequent cause of discomfort and often result in significant visual and functional impairment. The surgical management of these disorders includes various treatment options and techniques and is usually carried out in multiple time sessions. Case Report. We report the case of a 72 year old female patient, suffering from right eye involutional lower eyelid entropion and ptosis, who was treated synchronously for both conditions, by applying the lateral tarsal strip procedure and the levator resection technique. Conclusion. The synchronous treatment of involutional entropion and ptosis is an alternative treatment strategy, which could potentially improve surgical outcome, while reducing postoperative recovery time and treatment costs.

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3. When timing goes wrong

Circadian Rhythms: A Very Short Introduction ◽

10.1093/actrade/9780198717683.003.0003 ◽

2017 ◽

pp. 24-44

Author(s):

Russell G. Foster ◽

Leon Kreitzman

Keyword(s):

Circadian Rhythm ◽

Time Of Day ◽

Circadian System ◽

Multiple Time ◽

Sleep Phase ◽

Circadian Rhythm Sleep Disorders ◽

Time Zones ◽

Delayed Sleep Phase Disorder ◽

Delayed Sleep Phase ◽

Delayed Sleep

While time of day, interacting with an individual’s chronotype, can have an important impact upon performance and health, severe disruption of the circadian system adds another level of complexity and severity. ‘When timing goes wrong’ considers the effects of flying across multiple time zones, resulting in jet lag, and shift work on human health. Sleep and circadian rhythm disruption is almost always associated with poor health. Four circadian rhythm sleep disorders have been identified: advanced sleep phase disorder, delayed sleep phase disorder, freerunning, and irregular sleep timing. Sleep and circadian rhythm disruption in mental illness and neurodegenerative disease is also discussed.

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Concussion symptomology and recovery in children and adolescents with pre-existing anxiety

Journal of Neurology Neurosurgery & Psychiatry ◽

10.1136/jnnp-2020-323137 ◽

2020 ◽

Vol 91 (10) ◽

pp. 1060-1066 ◽

Cited By ~ 2

Author(s):

Alexia K Martin ◽

Ashley J Petersen ◽

Heather W Sesma ◽

Mary B Koolmo ◽

Katherine M Ingram ◽

...

Keyword(s):

Anxiety Disorders ◽

Children And Adolescents ◽

Symptom Severity ◽

Cox Regression ◽

Symptom Trajectories ◽

Severity Scores ◽

Symptom Load ◽

Prolonged Recovery ◽

Symptom Recovery ◽

Age And Sex

ObjectiveTo examine pre-existing anxiety disorders as a risk factor for increased concussion symptomology and prolonged recovery in children and adolescents.MethodsIn this retrospective cohort study, we abstracted medical record data for 637 children/adolescents (5–17 years) presenting to three tertiary concussion clinics between April 2018 and March 2019. Primary outcomes were mean concussion symptom and vision symptom severity scores measured at clinic visits. Linear mixed-effects regression models were employed to investigate differences in average symptom load, vision symptom score and symptom recovery trajectories across anxiety strata, adjusted for random effects (time), age and sex. Secondary outcomes, time to concussion symptom recovery and time to return to academics and sports, respectively, were examined via log-rank tests and multivariable Cox regression.ResultsAmong 637 eligible concussion patients, 155 (24%) reported pre-existing anxiety. On average, patients with anxiety reported an additional 2.64 (95% CI 1.84 to 3.44) concussion symptoms and 7.45 (95% CI 5.22 to 9.68) higher vision symptom severity scores throughout recovery versus those without, after adjusting for age and sex. There was no evidence that concussion or vision symptom trajectories varied over time between those with/without anxiety after accounting for baseline dissimilarities in symptom scores (all pinteraction >0.05). Anxiety was significantly associated with delayed symptom recovery (adjusted HR 3.34, 95% CI 2.18 to 5.12), return to school (adjusted HR 2.01, 95% CI 1.59 to 2.53) and return to physical activity (adjusted HR 1.88, 95% CI 1.49 to 2.37).ConclusionsPre-existing anxiety disorders were associated with more severe symptomology and prolonged recovery after concussion in children and adolescents. These results can be referenced by providers to manage patients’ recovery expectations.

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Utilizing the National Basketball Association’s COVID-19 restart “bubble” to uncover the impact of travel and circadian disruption on athletic performance

Scientific Reports ◽

10.1038/s41598-020-78901-2 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Andrew W. McHill ◽

Evan D. Chinoy

Keyword(s):

Athletic Performance ◽

Natural Experiment ◽

Circadian Disruption ◽

Multiple Time ◽

General Effect ◽

Professional Basketball ◽

Home Team ◽

Winning Percentage ◽

Time Zones ◽

The Impact

AbstractOn March 11th, 2020, the National Basketball Association (NBA) paused its season after ~ 64 games due to the Coronavirus 2019 (COVID-19) outbreak, only to resume ~ 5 months later with the top 22 teams isolated together (known as the “bubble”) in Orlando, Florida to play eight games each as an end to the regular season. This restart, with no new travel by teams, provided a natural experiment whereby the impact of travel and home-court advantage could be systematically examined. We show here that in the pre-COVID-19 regular season, traveling across time zones reduces winning percentage, team shooting accuracy, and turnover percentage, whereas traveling in general reduces offensive rebounding and increases the number of points the opposing (home) team scores. Moreover, we demonstrate that competition in a scenario where no teams travel (restart bubble) reduces the typical effects of travel and home-court advantage on winning percentage, shooting accuracy, and rebounding. Thus, home-court advantage in professional basketball appears to be linked with the away team’s impaired shooting accuracy (i.e., movement precision) and rebounding, which may be separately influenced by either circadian disruption or the general effect of travel, as these differences manifest differently when teams travel within or across multiple time zones.

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Jet Lag, Shift Work, and Maladaption

Physiology ◽

10.1152/physiologyonline.1986.1.5.156 ◽

1986 ◽

Vol 1 (5) ◽

pp. 156-160 ◽

Cited By ~ 1

Author(s):

MC Moore-Ede

Keyword(s):

Phase Shift ◽

Shift Work ◽

Circadian System ◽

Multiple Time ◽

Jet Lag ◽

Work Schedules ◽

Human Species ◽

Time Zones ◽

Rotating Shift Work ◽

Circadian Pacemakers

The circadian pacemakers, which time the approximately 24-h cycle of sleep and wakefulness, resynchronize only slowly after an abrupt phase shift in environmental time cues. Consequently, we are not well equipped to cope with jet travel across multiple time zones or with rotating shift work schedules, neither of which was in the evolutionary experience of the human species. Recent studies of the human circadian system suggest some strategies to minimize the ill effects of jet lag and shift work.

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Topical Antibiotic Elution in a Collagen-Rich Hydrogel Successfully Inhibits Bacterial Growth and Biofilm Formation In Vitro

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00136-20 ◽

2020 ◽

Vol 64 (10) ◽

Author(s):

Jung Gi Min ◽

Uriel J. Sanchez Rangel ◽

Austin Franklin ◽

Hiroki Oda ◽

Zhen Wang ◽

...

Keyword(s):

Cell Death ◽

Bacterial Growth ◽

Biofilm Formation ◽

Chronic Wounds ◽

Treatment Options ◽

Extracellular Proteins ◽

Multiple Time ◽

Content Type ◽

Biofilm Disruption

ABSTRACT Chronic wounds are a prominent concern, accounting for $25 billion of health care costs annually. Biofilms have been implicated in delayed wound closure, but they are susceptible to developing antibiotic resistance and treatment options continue to be limited. A novel collagen-rich hydrogel derived from human extracellular matrix presents an avenue for treating chronic wounds by providing appropriate extracellular proteins for healing and promoting neovascularization. Using the hydrogel as a delivery system for localized secretion of a therapeutic dosage of antibiotics presents an attractive means of maximizing delivery while minimizing systemic side effects. We hypothesize that the hydrogel can provide controlled elution of antibiotics leading to inhibition of bacterial growth and disruption of biofilm formation. The rate of antibiotic elution from the collagen-rich hydrogel and the efficacy of biofilm disruption was assessed with Pseudomonas aeruginosa. Bacterial growth inhibition, biofilm disruption, and mammalian cell cytotoxicity were quantified using in vitro models. The antibiotic-loaded hydrogel showed sustained release of antibiotics for up to 24 h at therapeutic levels. The treatment inhibited bacterial growth and disrupted biofilm formation at multiple time points. The hydrogel was capable of accommodating various classes of antibiotics and did not result in cytotoxicity in mammalian fibroblasts or adipose stem cells. The antibiotic-loaded collagen-rich hydrogel is capable of controlled antibiotic release effective for bacteria cell death without native cell death. A human-derived hydrogel that is capable of eluting therapeutic levels of antibiotic is an exciting prospect in the field of chronic wound healing.

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